TypeScript高级类型在鸿蒙中的使用 Partial、Required、Readonly、Pick、Record

news2024/9/17 8:27:41

我的工程代码在这里，持续更新中
欢迎交流，谢谢
https://github.com/MartinLi89/WanHarmony

Partial <Type>

新定义一个类型，将所有属性变为可选的类.

class TextTS {
  a: string = "1"
  b: string = "2"
  c: string = "3"
}

//1 Partial <Type>新定义 一个类型，将所有属性变为可选的类
type PartialTextTs = Partial<TextTS>
let test2: TextTS = {
  //报错 ,说明属性必填
  a:  "1",
  b:  "2",
  c:  "3"
}
let test1: PartialTextTs = {
  //正常，说明属性可选
}

Required <Type>

新定义一个类型，将所有属性变为必选的类

//1.1 Required
type Person =  Required<TextTS>
let test3: Person = {
  a : "1",
  b : "2",
  c : "3"

}

Readonly<Type>

新定义一个类型，将所有属性变为只读的类

//2Readonly <Type> 新定义 一个类型， 将所有属性变为只读的类
type ReadonlyTextTs = Readonly<TextTS>
let testReadonly: ReadonlyTextTs = {
  a: "1",
  b: "2",
  c: "3"
}
let test12: TextTS = {
  a: "1",
  b: "2",
  c: "3"
}
testReadonly.a = "f" //报错，说明只读
test12.a = "f"

Pick<Type,Keys>

新定义一个类型从Type类型中，选择需要的keys，构成新的类型
这是不支持么，居然报错
Some of utility types are not supported (arkts-no-utility-types) <ArkTSCheck>
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Record<Keys,Type>

新定义一个类型属性键为Keys，属性类型为Type，构成新的类型居然报错
Object literal must correspond to some explicitly declared class or interface (arkts-no-untyped-obj-literals) <ArkTSCheck>
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